In the meat industry, it is desired to obtain as much edible meat as possible from each slaughtered animal. However, high labor costs make it uneconomical to cut away small pieces of meat adhering to bones, and particularly irregular bones such as vertebrae.
Nevertheless, such small pieces of meat are wholesome and may be used, if recovered, in communited meat products, such as hamburger meat, sausages, pieced and formed "steaks" and beef rolls.
It has been proposed to separate meat, and particularly chicken meat, from bones by the action of high velocity water jets. Downs U.S. Pat. No. 3,671,999, for example, discloses placing poultry pieces cooked on a mesh conveyor, directing high velocity water jets against the poultry pieces from both above and below the top flight of the conveyor and thereby separating meat pieces from the bones of the poultry pieces, and permitting the meat pieces to fall through the conveyor while the bones are conveyed to the end thereof.
Geisler U.S. Pat. Nos. 2,734,537 and 2,734,540 relate, respectively, to method and apparatus for separating meat from bones and disclose the use of high velocity jets which may be either water jets or air jets. When air jets are used there is a drying action on the meat and the bones.
The use of water jets, as disclosed in the prior art, adds water to the separated meat pieces, increasing their weight and thereby bringing such use into conflict with quality standards and with government regulations. The use of air jets is less effective than water jets in separating meat from bone and also, as indicated by the Geisler patents, dries the meat pieces.
Lindall U.S. Pat. No. 3,089,775 discloses a method for removing meat from bone by "shot blasting" with solid frozen particles of ice or carbon dioxide carried in a stream of high velocity air. Both ice and solid carbon dioxide are relatively expensive and their use adds to the cost of the process and makes it less attractive.